The present invention relates to a magnetic mirror for beams of charged particles, this magnetic mirror, which is designed to be used in association with an accelerator of charged particles (electrons for example) having variable energy, enabling the beam of charged particles to be passed twice through the accelerating structure.
Accelerators using a magnetic mirror are early described by the U.S. Pat. No. 4,004,181 as well as in the publications of G. Hortig and A. A. Kolomenski, and designed so as to ensure the isochronism of the reflected and incident beams. This results in a magnetic mirror relatively complex, but the isochronism of the outgoing and return beams enables the accelerated beam issued from this accelerator to be a beam of very fine spectrum, since the beam is always accelerated on the peak of the electromagnetic wave generated in the accelerating cavities.
However, it appears that, if a charged particle accelerator is caused to function in such a way that the beam is accelerated on the outgoing and return path respectively on the two edges located on either side of the peak of the accelerating electromagnetic wave, this makes it possible to alleviate the demand for perfect isochronism of the outward and return beams, thus no longer requiring mechanical displacement of the mirror in relation to the accelerator, which is generally necessary when the energy of the beam of particles is modified. This mechanical displacement is then replaced by the phase shifting provided by the magnetic mirror, to which the invention relates, as a function of the energy of said particles.